Beamforming is a signal processing technique used with sensor arrays for directional signal transmission or reception. Spatial selectivity is achieved by using adaptive or fixed receive/transmit beam patterns. Beamforming can be used for both electromagnetic waves (e.g., RF) and acoustic waves, and has found a variety of applications in radar, seismology, sonar, wireless communications, radio astronomy, speech, and medicine. Adaptive beamforming is used to detect and estimate the signal-of-interest at the output of a sensor array using data-adaptive spatial filtering and interference rejection.
Ultrasound imaging applications may use beamforming at the transmitter and/or the receiver. In medical imaging applications, ultrasound energy may be focused at target tissue by a transmit beamformer, and ultrasound energy modulated and returned by the target tissue may be focused by a receive beamformer. The receive beamformer may provide signals for generation of brightness (B-mode) images, and/or color Doppler or spectral Doppler information representing the target tissue, or combinations thereof. Ultrasound beamforming systems can provide real-time, cross-sectional (tomographic) two-dimensional images or three-dimensional images of human or animal tissue, or other objects of interest.